Over the years, there have been a large variety of proposals for the retrieval of water from wells that operate on naturally occurring energy. The most typical of such proposals is, of course, the windmill.
While in many instances, particularly where shallow wells are concerned, such proposals have operated satisfactorily, as the depth of the well increases, more work must be required to elevate water to the surface with the result that the apparatus or system necessary to form such elevation must necessarily increase in size. This, of course, increases the cost of the system.
Technological improvements over the years have in a variety of fields suggested that greater reliability of particular systems can be obtained by moving away from a wholly mechanical approach to one which minimizes the number of mechanical components involved. And at the same time, there is ever increasing concern for the conservation of energy and interest in economical utilization of naturally occurring forms of energy, particularly those in wave form such as sunlight and in kinetic form such as that contained in fluids undergoing movement due to natural causes.
These concerns have in turn resulted in considerable focus on electrical generation or conversion devices for converting such naturally occurring forms of energy into electrical energy as, for example, by photovoltaic cells or so-called "solar panels", wind driven generators and the like. While both in theory and in practice, state of the art technology is such that such generators can be employed to provide energy for the retrieval of water from wells, because energy requirements increase as the depth of the well increases, for many wells the cost of providing such an energy source with sufficient capacity to drive a large pump is so prohibitive as to make such a system thoroughly economically impractical though technically quite feasible.